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Cost-utility and cost-effectiveness analyses of a long-term high-intensity exercise program compared with conventional physical therapy in patients with rheumatoid arthritis.

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Arthritis & Rheumatism (Arthritis Care & Research)
Vol. 53, No. 1, February 15, 2005, pp 39 – 47
DOI 10.1002/art.20903
© 2005, American College of Rheumatology
ORIGINAL ARTICLE
Cost-Utility and Cost-Effectiveness Analyses of a
Long-Term, High-Intensity Exercise Program
Compared With Conventional Physical Therapy in
Patients With Rheumatoid Arthritis
WILBERT B. VAN DEN HOUT, ZUZANA DE JONG, MARTEN MUNNEKE, JOHANNA M. W. HAZES,
FERDINAND C. BREEDVELD, AND THEODORA P. M. VLIET VLIELAND
Objective. To estimate the cost utility and cost effectiveness of long-term, high-intensity exercise classes compared with
usual care in rheumatoid arthritis (RA) patients.
Methods. RA patients (n ⴝ 300) were randomly assigned to either exercise classes or UC; followup lasted for 2 years.
Outcome measures were quality-adjusted life years (QALYs) according to the EuroQol (EQ-5D), Short Form 6D (SF-6D),
and a transformed visual analog scale (VAS) rating personal health; functional ability according to the Health Assessment
Questionnaire (HAQ) and McMaster Toronto Arthritis Patient Preference Interview (MACTAR); and societal costs.
Results. QALYs in both randomization groups were similar according to the EQ-5D and SF-6D, but were in favor of usual
care according to the VAS (annual difference 0.037 QALY; 95% confidence interval [95% CI] 0.002, 0.069). Functional
ability was similar according to the HAQ, but in favor of the exercise classes according to the MACTAR (annual difference
2.9 QALY; 95% CI 0.9, 4.9). Annual medical costs of the exercise program were estimated at €780 per participating patient
(€1 ⬇ $1.05). The increase per patient in total medical costs of physical therapy was estimated at €430 (95% CI €318, 577),
and the increase in total societal costs at €602 (95% CI €ⴚ490, 1,664). For societal willingness-to-pay equal to €50,000 per
QALY, usual care had better cost utility than exercise classes, and significantly so according to the VAS.
Conclusion. From a societal perspective and without taking possible preventive health effects into account, long-term,
high-intensity exercise classes provide insufficient improvement in the valuation of health to justify the additional costs.
KEY WORDS. Cost-utility analysis; Cost-effectiveness analysis; Economic evaluation; Physical therapy; Exercise classes;
Rheumatoid arthritis.
INTRODUCTION
It has long been accepted that physical activity improves
health by preventing mortality and morbidity from cardiovascular diseases, osteoporosis, anxiety, and depression
(1–3). Increasingly, exercise programs are developed and
Wilbert B. van den Hout, PhD, Zuzana de Jong, MD, Marten Munneke, PT, MSc (current address: University Medical
Center St. Radboud, Nijmegen, The Netherlands), Johanna
M. W. Hazes, MD, PhD (current address: Rotterdam University Hospital, Rotterdam, The Netherlands), Ferdinand C.
Breedveld, MD, PhD, Theodora P. M. Vliet Vlieland, MD,
PhD: Leiden University Medical Center, Leiden, The Netherlands.
Address correspondence to Wilbert B. van den Hout, PhD,
Department of Medical Decision Making J10-S, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The
Netherlands. E-mail: Hout@LUMC.NL.
Submitted for publication August 1, 2003; accepted in
revised form May 19, 2004.
implemented for specific patient groups. For rheumatoid
arthritis (RA) patients, despite their increased susceptibility for the mentioned comorbidities (4 – 6), exercise programs have for a long time included only low-intensity
training aimed at preserving joint mobility. Patients were
discouraged from performing intensive physical activity,
for fear of damage to the large joints and exacerbation of
joint inflammation (7).
Only relatively recently, it was shown that RA patients
benefit from both short-term (8 –10) and long-term (11)
high-intensity exercise, without worsening of inflammation or progression of joint damage. This was confirmed by
the Rheumatoid Arthritis Patients In Training (RAPIT)
study (12) that compared a long-term, high-intensity exercise program with usual care consisting of individual
physical therapy only if regarded necessary by the attending physician. The study demonstrated that RA patients
were able to improve their functional ability, physical
capacity, emotional status, and bone mineral density,
39
40
van den Hout et al
Table 1. Eligibility criteria for participation in the
RAPIT trial*
● Age 20–70 years
● Rheumatoid arthritis according to 1987 ACR criteria
(43)
● ACR functional class I–III (44)
● Stable disease-modifying antirheumatic drugs in past 3
months
● Able to cycle
● Willing to exercise biweekly on fixed schedule
● Living within a predefined adherence region of training
or assessment center
● No prosthesis of a weight-bearing joint
● No cardiopulmonary disease precluding intensive
exercise
● No comorbidity causing a short life expectancy
● No serious psychiatric disease
● Able to complete a questionnaire
* RAPIT ⫽ Rheumatoid Arthritis Patients in Training; ACR ⫽
American College of Rheumatology (formerly American Rheumatism Association).
without an increase in disease activity or additional damage to the large joints. However, studies have so far not
reported on whether these exercise programs provide good
value for money from the societal perspective. Here we
will present the economic evaluation of the RAPIT study,
estimating the cost utility and cost effectiveness of longterm, high-intensity exercise classes compared with usual
care, in RA patients.
PATIENTS AND METHODS
The RAPIT study was a multicenter, single-blinded randomized controlled trial (12), comparing safety, effectiveness, and costs of a long-term intensive exercise program
(RAPIT) with those of usual care physical therapy. Patients
registered in 2 university and 2 nonuniversity outpatient
rheumatology clinics in the Netherlands were invited to
participate. In May and June 1998, 300 RA patients who
fulfilled the eligibility criteria for the trial (Tables 1 and 2)
were included and randomized to receive the RAPIT program or usual care.
Intervention. The RAPIT program consisted of longterm, high-intensity weight-bearing exercise classes aimed
at maintaining and improving physical ability. Patients
participated in the group exercise classes for 2 years, with
two 75-minute sessions each week. In general, sessions
consisted of warming up, bicycle training, an exercise
circuit, sport or game, and cooling down. The classes were
supervised by 2 physical therapists and, on average, consisted of 14 patients. Patients were encouraged to communicate possible physical problems with the physical therapists and, if necessary, the program was adapted to
individual needs. Patients in the control group received
usual care, consisting of individual physical therapy, only
if this was regarded necessary by the attending physician.
Assessments of utility. Utility is the valuation of the
health of the patient (13), ranging from 0 (as bad as death)
to 1 (full health), and was assessed in 3 different ways
every 6 months, using questionnaires that were filled out
by the patients without supervision. Patients described
their general health status using the EuroQol classification
system (EQ-5D), consisting of 5 questions on mobility, self
care, usual activities, pain/discomfort, and anxiety/depression (14). From the EQ-5D classification system, the
EQ-5D utility index was calculated (15). This utility measure reflects how the general public values the health
status described by the patient, which is preferred for
economic evaluations from a societal perspective.
Quality of life was also assessed using the RAND-36
questionnaire (16). The RAND-36 consists of 36 items on
physical and social functioning, role limitations, mental
health, vitality, pain, and general health perception. From
the RAND-36, the Short Form 6D (SF-6D) utility index was
calculated (17). Like the EQ-5D, this SF-6D reflects the
general public’s valuation of the health described by the
patient. The SF-6D is a recent instrument that has not been
Table 2. Trial flow and baseline characteristics of 300 RA patients with baseline assessment*
Randomized patients, n (%)
Baseline assessments, n (%)
In study after 2 years, n (%)
In RAPIT program after 2 years, n (%)
Age, median (IQR) years
Female, n (%)
Duration of RA, median (IQR) years
Rheumatoid factor positive, n (%)
Radiologic damage hands and feet, median (IQR)
Past number of DMARDs, mean ⫾ SD
DMARDs, n (%) of users
Oral corticosteroids, n (%) of users
Intraarticular corticosteroids, n (%) of users
RAPIT
UC
P†
151 (100)
150 (99)
136 (90)
114 (75)
54.0 (16)
119 (79)
5.0 (7)
107 (71)
25.0 (53.8)
1.8 ⫾ 1.5
117 (78)
12 (8)
17 (11)
158 (100)
150 (95)
145 (92)
—
53.5 (18)
118 (79)
7.5 (10.8)
106 (71)
38.5 (54.5)
2.0 ⫾ 1.2
134 (89)
15 (10)
7 (5)
—
0.02
0.03‡
—
0.96
1.00
0.01
1.00
0.03
0.77
0.01
0.55
0.06
* RA ⫽ rheumatoid arthritis; RAPIT ⫽ Rheumatoid Arthritis Patients in Training exercise program; UC ⫽ usual care; IQR ⫽ interquartile range;
DMARDs ⫽ disease-modifying antirheumatic drugs.
† Mann-Whitney U test or ␹2 test where appropriate.
‡ Tested among patients with baseline assessment.
CUA Exercise Classes
used much, but its richer classification system could make
it a more sensitive utility measure than the EQ-5D.
Patients rated their personal health using a visual analog
scale (VAS) ranging from worst imaginable health to best
imaginable health. Because the VAS has repeatedly been
found to render less favorable valuations than more valid
(but also more complicated) utility measures, the obtained
VAS values were transformed using the power function
1–(1–VAS)1.61 (18,19). Because patients experience all the
subtleties of their health status, the VAS is potentially
more sensitive to change, but it is not preferred for economic evaluations from a societal perspective (20).
Assessments of functional ability. The primary clinical
endpoint of the RAPIT study was functional ability, assessed every 6 months by the Health Assessment Questionnaire (HAQ) and by the McMaster Toronto Arthritis
Patient Preference Interview (MACTAR). The HAQ consists of 20 questions concerning 8 domains of problems in
the activities of daily living (21,22). The total HAQ score
ranges from 0 (without any difficulty) to 3 (unable to do).
The MACTAR is a semistructured interview, assessed by a
trained interviewer, consisting of status and transitional
questions (23,24). The status questions elicit the patient’s
health status through 5 questions on general health; satisfaction with quality of life; and physical, social, and emotional wellbeing. The transitional questions focus on perceived change in disease activity and change in ability to
perform a set of 5 impaired activities. These activities were
selected and ranked by each individual patient at the
beginning of the study. To improve sensitivity to relevant
change, a new set of activities could be chosen after a year
if the original activities were no longer impaired or no
longer of interest to the patient. The MACTAR scores
during the second year were calculated by adding the
MACTAR score at the end of the first year to the change
during the second year. The weighted MACTAR score
ranges from 21 to 77 points, with higher scores reflecting
better functional ability.
Assessment of costs. Societal costs during the 2-year
followup period were assessed in strict accordance to current guidelines for economic evaluations (25). The estimated costs included the costs of the RAPIT program,
other medical costs (like individual physical therapy and
hospitalizations), and nonmedical costs (like time, travel,
and informal care). Costs of the RAPIT program and of
disease-modifying antirheumatic drugs were estimated
from the study registration. All other costs were estimated
from quarterly cost questionnaires filled out by the patients. Costs were not discounted, to facilitate averaging
over the short 2-year study period. Costs are reported as
annual costs, converted to price level 2002 euros using the
price index rate for the Dutch health care sector (obtained
from Statistics Netherlands). Euros can be converted to US
dollars using the Dutch purchasing power parity index for
2004: €1 ⫽ $1.05 (available at: www.oecd.org).
Costs of the RAPIT program. The costing analysis of the
RAPIT program was based on experience acquired during
41
the study. The classes were organized by 2 physical therapists. Each class took them 100 minutes, of which 25
minutes were for traveling and preparation and 75 minutes
were for the classes themselves. This time was valued at
€25.60 per hour, i.e., the income component of the Dutch
reimbursement for individual physical therapy (available
at: www.ctgzorg.nl). Because physical therapists obtain
their income from these reimbursements, they are a reasonable reflection of the true costs for physical therapists.
The exercise classes are assumed to take place in gyms,
rented at €27 per class. This includes the costs for simple
materials and 7 exercise bikes.
An exercise class, on average, consisted of 14 patients,
with 94 planned classes per year of 75 minutes each.
Patients, on average, attended 72% of the classes. For
individual patients, costs for the exercise classes were
counted for as long as the patient remained in the program.
Time and travel costs were included in analyses from a
societal perspective. Time costs were estimated at 95 minutes per patient per class, valued at €5 per hour (26).
Travel costs were estimated at €3 per patient per class.
Other medical costs. In the quarterly cost questionnaires, patients reported physical therapy other than the
RAPIT program, consultations (general practitioner visits,
specialist consultations, paramedical professionals other
than physical therapists, and alternative medicine), hospitalizations, home nursing care, and purchased medication.
Most cost prices were obtained from Dutch standard prices
that were designed to reflect societal costs and to standardize economic evaluations (27,28). Physical therapy other
than the RAPIT program was valued at €47 per hour
(www.ctgzorg.nl). The general practitioner was valued at
€18 per consultation (27), half for telephone, and double
for home consultations. Specialist consultations were on
average valued at €49 (27), ranging from €25 to €76 for
different specialties. Paramedical professionals other than
physical therapists were valued at €20 per consultation
(27), and alternative medicine, on average, at €29 per consultation. Day care hospitalizations in rheumatology departments were valued at €758 per admission plus €236
per day, and clinical hospitalizations at €909 per admission plus €243 per day (26). Other hospitalizations were
valued at €431 per day for nonuniversity hospitals and
€599 per day for university hospitals (27,29). Home nursing care was valued at €34 per hour (27). Purchased medication was valued according to the Pharmacotherapeutic
Compass (28), plus €6 for each purchase other than overthe-counter medications (27).
Nonmedical costs. Nonmedical costs included time and
travel costs required to obtain health care, sports expenses,
other out-of-pocket costs (like special appliances and
house adaptations), absenteeism, unpaid labor, domestic
help, and informal care. Time was valued at €5 per hour
(26), with the amount of time varying from 10 minutes per
telephone consultation to 8 hours per hospitalization day.
Travel was valued at €1.22 plus €0.29 per kilometer, with
national averages for the travel distances to different types
of medical care. Sports expenses and other out-of-pocket
42
van den Hout et al
costs were valued as reported by the patients. Paid labor
was valued using the friction cost method in which productivity costs are calculated for at most 4 months, which
is the estimated time needed to find a replacement (30).
Time spent on unpaid labor was compared with the average over the entire sample (for men and women separately,
corrected for the individual amount of domestic and informal care), and the difference was valued at €5 per hour
(the value of time). With this method, patients who reported more unpaid labor than average have negative costs
(profits). Domestic help was valued at €19 per hour (27),
and reported informal care was valued at minimum wages
(€9 per hour, with a maximum of 28 hours per week).
Analysis. All patients were evaluated according to intention to treat, with correction for baseline differences (by
subtracting from all effectiveness scores the individual
baseline score and adding the overall average baseline
score). Missing measurements were imputed by carrying
forward the last available previous measurement. On average, 4% of the utility measurements, 4% of the HAQ
measurements, 6% of the MACTAR measurements, and
8% of the cost questionnaires were missing, with missing
measurements about twice as frequent in the RAPIT group.
Because in economic evaluations it is sustained improvement that counts, not the separate measurements but
the areas under the measurement curves were used in the
analyses. For utility measures, the area under the curves is
known as quality-adjusted life years (QALYs). QALYs are
an accepted measure for resource allocation decisions involving diverse treatments and patient populations. Costeffectiveness analyses with QALYs as a measure of effectiveness are known as cost-utility analyses.
In our economic evaluation, both randomization groups
were compared with respect to their net benefit (31) by
subtracting the costs associated with the interventions
from society’s willingness to pay (WTP) for the obtained
effectiveness:
Net benefit ⫽ (effectiveness ⫻ WTP) ⫺ costs
This net benefit was calculated for each patient individually. The more cost-effective treatment is the one with the
higher average net benefit, which also depends on the
value of the WTP. If one treatment is more effective than
the other at higher costs, then the differences in costs
divided by the difference in effectiveness is called the
incremental cost-effectiveness ratio (ICER) of the treatment
under investigation.
According to the original study protocol, the primary
economic evaluation compared 2-year QALYs based on
the EQ-5D with 2-year total societal costs. Sensitivity analysis was, however, also performed by considering different
utility and effectiveness measures (EQ-5D, SF-6D, VAS,
HAQ, and MACTAR) and different cost measures (total
societal costs and societal costs of all physical therapy).
For all outcome measures, differences between the randomization groups were tested using double-sided bootstrapping (32), with 1,000,000 replications and 0.05 significance threshold. Reported confidence intervals are the
corresponding 95% trimmed asymmetric confidence inter-
Figure 1. Utility measures. VAS ⫽ visual analog scale; SF-6D ⫽
Short Form 6D; EQ-5D ⫽ EuroQol 5D; RAPIT ⫽ Rheumatoid
Arthritis Patients In Training; UC ⫽ usual care.
vals (95% CIs). Bootstrapping explicitly compares the
means in both groups, without making distributional assumptions and thus allowing for skewed distributed costs.
RESULTS
Utility and effectiveness analyses. Compared with the
usual care group, the average valuation of health (utility)
in the RAPIT group was somewhat more favorable according to the SF-6D measure, but was less favorable according
to the EQ-5D and the VAS measures (Figure 1). Over the
2-year followup period, only the difference according to
the VAS was significant (Table 3), with an estimated annual difference of 0.037 QALY in favor of usual care (95%
CI 0.002, 0.069).
Patients in the RAPIT group showed a larger improvement in functional ability according to both the HAQ and
the MACTAR (Figure 2). Over the 2-year period, the difference on the MACTAR was significant (Table 3), with an
estimated annual difference of 2.9 (95% CI 0.9, 4.9).
Costs of the RAPIT program. The medical costs of the
RAPIT program were estimated at €10,800 per group annually, of which 24% was for materials and accommodation and 76% for the 2 physical therapists (160 hours per
therapist annually). With, on average, 14 patients per
group, these estimated costs amount to €780 per patient.
Based on 94 planned sessions per year with 72% attendance of patients, the costs per patient per attended class
were €11.40. If supervision would be provided by only a
single physical therapist, or by a single therapist assisted
by a trained lay person valued at minimum wages, then the
medical costs of the RAPIT program could be reduced by
35% and 23%, respectively.
From a societal perspective, costs also include the patients’ invested time and travel costs. These costs
amounted to €7,100 (for 107 hours per patient annually)
and €2,600, respectively. This almost doubled the costs of
the exercise classes to €20,500 per group annually.
CUA Exercise Classes
43
Table 3. Average QALYs and functional ability per patient*
QALYs, based on EQ-5D
Year 1
Year 2
Average
QALYs, based on SF-6D
Year 1
Year 2
Average
QALYs, based on VAS
Year 1
Year 2
Average
HAQ
Year 1
Year 2
Average
MACTAR
Year 1
Year 2
Average
RAPIT
UC
Difference
P†
0.633 (0.130)
0.627 (0.192)
0.630 (0.150)
0.666 (0.142)
0.651 (0.186)
0.659 (0.153)
⫺0.033
⫺0.024
⫺0.029
0.04
0.27
0.11
0.682 (0.058)
0.683 (0.083)
0.682 (0.065)
0.671 (0.078)
0.676 (0.103)
0.673 (0.084)
0.011
0.007
0.009
0.15
0.55
0.31
0.767 (0.127)
0.752 (0.129)
0.759 (0.145)
0.795 (0.137)
0.797 (0.192)
0.796 (0.149)
⫺0.028
⫺0.045
⫺0.037
0.07
0.04
0.03
0.743 (0.206)
0.740 (0.328)
0.741 (0.251)
0.740 (0.252)
0.793 (0.292)
0.766 (0.254)
0.003
⫺0.053
⫺0.025
0.90
0.14
0.39
1.4
4.5
2.9
0.08
0.002
0.005
54.4 (7.0)
56.8 (12.4)
55.6 (9.2)
53.0 (6.2)
52.3 (12.0)
52.7 (8.5)
* Values are the mean (SD). QALYs ⫽ quality-adjusted life years, ranging from 0 (worst) to 1 (best);
RAPIT ⫽ Rheumatoid Arthritis Patients in Training exercise program; UC ⫽ usual care; EQ-5D ⫽ EuroQol
classification system; SF-6D ⫽ Short Form 6D; VAS ⫽ transformed visual analog scale rating personal
health; HAQ ⫽ Health Assessment Questionnaire, ranging from 0 (without any difficulty) to 3 (unable to
do); MACTAR ⫽ McMaster Toronto Arthritis Patient Preference Interview, ranging from 21 (worst) to 77
(best).
† Double-sided bootstrapping.
Costs of all physical therapy per patient. Because participation gradually decreased over time, the average medical costs per patient for the RAPIT program decreased
from €733 in the first year to €634 in the second year
(Figure 3, Table 4). In both randomization groups, patients
could seek individual physical therapy. During the first
quarter, the medical costs for individual physical therapy
were comparable, but later on they were considerably
lower for the RAPIT patients. Over the 2-year period, the
medical costs for individual physical therapy were reduced by 62%, which partly compensated the costs of the
RAPIT program. Nevertheless, the annual medical costs of
all physical therapy (both the RAPIT program and individ-
Figure 2. Effectiveness measures. HAQ ⫽ Health Assessment
Questionnaire; RAPIT ⫽ Rheumatoid Arthritis Patients In Training; UC ⫽ usual care; MACTAR ⫽ McMaster Toronto Arthritis
Patient Preference Interview.
ual physical therapy) were still €430 in favor of usual care
(95% CI €318, 577). Including time and travel costs, the
annual difference in societal costs of all physical therapy
was €996 (95% CI €860, 1,170).
Total societal costs per patient. All medical and nonmedical cost categories that were not directly associated
with physical therapy did not show a significant difference
between the randomization groups (Table 4). Patients in
the RAPIT group did report considerably more out-ofpocket costs, which was mainly due to house adaptations
(annual cost difference €312, 95% CI €⫺84, 585). On the
other hand, they also reported more unpaid labor than the
Figure 3. Medical costs of all physical therapy per quarter (purchasing power parity index: €1 ⫽ $1.05). RAPIT ⫽ Rheumatoid
Arthritis Patients In Training; UC ⫽ usual care.
44
van den Hout et al
Table 4. Average annual health care consumption and costs per patient*
RAPIT
Medical costs
RAPIT program, classes
Individual physical therapy, hours, %
Rheumatologists, visits
Other specialists, visits
General practitioner, visits
Paramedical professionals, visits§
Alternative medicine, visits
Hospitalizations, %
Home nursing care, hours
Medication
Total medical costs (SD)
Nonmedical costs
T&T RAPIT program, hours
T&T individual physical therapy, hours
T&T other medical care, hours
Sports expenses
Other out-of-pocket
Paid labor; %, hours/week
Absenteeism, hours/week
Unpaid labor, hours/week
Home help, hours/week
Informal care, hours/week
Total nonmedical costs (SD) hours/week
Total societal costs (SD)
UC
Volume
Cost in ۠
Volume
Cost in ۠
P‡
60
3.2, 23
4.8
2.4
5.5
1.0
1.0
20
0.3
684
155
279
94
91
53
29
607
22
102
2,115 (2,125)
—
8.4, 45
4.7
2.5
4.2
0.9
0.9
22
0.1
—
408
271
98
72
45
25
602
8
154
1,683 (1,968)
⬍ 0.001
0.001
0.66
0.80
0.06
0.60
0.73
0.98
0.35
0.07
0.07
95
3
37
616
31
253
8
730
—
121
⫺270
782
362
2,634 (4,120)
4,749 (4,953)
—
—
81
243
20
406
—
155
270
884
405
2,464 (3,877)
4,147 (4,497)
⬍ 0.001
⬍ 0.001
0.76
0.06
0.06
—
0.44
0.17
0.54
0.73
0.71
0.27
33, 24
0.7
26
0.7
0.8
—
—
8
36
42, 25
0.7
23
0.9
0.9
—
* RAPIT ⫽ Rheumatoid Arthritis Patients in Training exercise program; UC ⫽ usual care; T&T ⫽ time and travel.
† Purchasing power parity index: €1 ⫽ $1.05.
‡ Double-sided bootstrapping.
§ Paramedical professionals other than physical therapists.
usual care group (annual cost difference €540, 95% CI
€⫺240, 1,310). The estimated annual difference in total
societal costs was €602 per patient (95% CI €⫺490, 1,664).
Cost-utility and cost-effectiveness analyses. The primary economic evaluation of the RAPIT study was the
cost-utility analysis comparing the €602 difference in total
societal costs to the 0.029-year difference in QALYs based
on the EQ-5D. If society values QALYs at (the often
quoted) €50,000 per QALY, then the difference in net
benefit is 0.029 ⫻ €50,000 ⫹ €602 ⫽ €2,052 per patient
annually. Because both costs and QALYs are in favor of
usual care, the net benefit is also in favor of usual care,
regardless society’s WTP. The difference in net benefit did
not reach statistical significance for any WTP (P ⱖ 0.06,
with P ⫽ 0.06 for WTP ⫽ €50,000 and P ⬍ 0.10 for
€16,000 ⱕ WTP ⱕ €1,200,000).
In sensitivity analyses, we considered other utility
(SD-6D and VAS), effectiveness (HAQ and MACTAR), and
costs measures. According to the SF-6D, patients in the
RAPIT program had higher QALYs than patients receiving
usual care. The additional total societal costs of €602 rendered a 0.009 QALY improvement, with an estimated ICER
of €67,000 per QALY. However, the net benefit was again
not significantly different for any WTP (P ⱖ 0.27 and P ⫽
0.83 for WTP ⫽ €50,000).
According to the VAS, patients in the RAPIT program
had lower QALYs than patients receiving usual care, so
cost utility was in favor of usual care for all levels of
society’s WTP. Here, the difference was significant for all
WTP above €19,000 per QALY (P ⱕ 0.05 and P ⫽ 0.02 for
WTP ⫽ €50,000).
Both measures of functional ability were in favor of the
RAPIT program. For the HAQ, the ICER was estimated at
€24,000 per HAQ point, but the net benefit was not significantly different for any WTP (P ⱖ 0.27). For the MACTAR,
the ICER was estimated at €210 per MACTAR point, and
the net benefit was significantly different for WTP greater
than €1,200 per MACTAR point (P ⱕ 0.05).
We also performed sensitivity analyses including only
the costs associated with physical therapy because all
other cost categories showed no significant difference. The
results basically remained the same, except that the reduced variability in costs considerably increased the statistical significance of the economic differences in favor of
usual care, and the estimated ICERs were less favorable for
the RAPIT program by 66% (Table 5).
DISCUSSION
In line with previous studies (3), the RAPIT study has
shown that for RA patients a long-term, high-intensity
exercise program is safe and effective in improving phys-
CUA Exercise Classes
45
Table 5. Cost-utility and cost-effectiveness analyses of the RAPIT exercise program compared with usual care for different
utility, effectiveness, and cost measures*
Estimated result
Total societal costs
EQ-5D†
SF-6D
VAS
HAQ
MACTAR
Societal costs of all
physical therapy¶
EQ-5D
SF-6D
VAS
HAQ
MACTAR
Statistical significance of difference in net benefit†
UC better cost utility for all WTP
ICER €67,000 per QALY‡§
UC better cost-utility for all WTP
ICER €24,000 per HAQ point
ICER €210 per MACTAR point
Not significant for any WTP
Not significant for any WTP
Significant for WTP ⱖ€19,000 per QALY
Not significant for any WTP
Significant for WTP ⱖ€1,200 per MACTAR point
UC better cost utility for all WTP
ICER €110,000 per QALY
UC better cost utility for all WTP
ICER €40,000 per HAQ point
ICER €340 per MACTAR point
Significant for WTP ⱕ€160,000 per QALY
Significant for WTP ⱕ€37,000 per QALY
Significant for all WTP
Significant for WTP ⱕ€12,000 per HAQ point
Significant for WTP ⱕ€190 per MACTAR point
and for WTP ⱖ€1,100 per MACTAR point
* RAPIT ⫽ Rheumatoid Arthritis Patients in Training exercise program; EQ-5D ⫽ EuroQol classification system; UC ⫽ usual care; WTP ⫽ willingness
to pay; SF-6D ⫽ Short Form 6D; VAS ⫽ transformed visual analog scale rating personal health; HAQ ⫽ Health Assessment Questionnaire; MACTAR ⫽
McMaster Toronto Arthritis Patient Preference Interview; ICER ⫽ incremental cost-effectiveness ratio.
† Primary economic analysis, all others are sensitivity analyses.
‡ Net benefit ⫽ (effectiveness ⫻ WTP) ⫺ costs. Cost effectiveness is in favor of the RAPIT program for WTP below the ICER, and is in favor of UC for
WTP above the ICER.
§ Purchasing power parity index: €1 ⫽ $1.05.
¶ RAPIT exercise program and individual physical therapy, including time and travel costs.
ical capacity and emotional status, without an increase in
disease activity or radiographic joint damage (12). It also
proved to be effective in improving functional ability and
in slowing down age-related bone loss. In the economic
evaluation reported here, we studied whether from the
societal perspective clinical effectiveness is attained at
reasonable costs.
The costs of exercise programs can vary considerably,
depending on the number of participating patients, the
accommodation, and the agreed income of the physical
therapists. In the Dutch setting, the annual medical costs
were estimated at €10,800 per RAPIT group, which is €780
per participating patient (€1 ⬇ $1.05). The additional time
and travel costs incurred by the patients almost doubled
these costs and can seriously discourage participation by
the patients. Costs of the RAPIT program were partly compensated by a decrease in individual physical therapy. As
a result, the annual increase in medical costs of all physical therapy for patients participating in the RAPIT program was estimated at €430. The annual increase in total
societal costs was estimated at €602 per patient. More
research is needed on the development of less expensive
exercise interventions. If effectiveness could be maintained with less therapists’ supervision and more homebased exercises, this would cut down on costs. However,
until now, home-based exercise programs designed for
patients with RA did prove effective with respect to the
improvement of physical capacity but, perhaps due to
their low intensity or lack of impact, did not accomplish
significant changes in functional capacity or bone mineral
density (11,33,34).
For policy making from a societal perspective, costs
need to be weighed against an effectiveness measure that is
applicable and comparable for a wide range of diseases
and treatments. The 3 QALY measures used in our study
satisfy this requirement and, despite their conceptual differences, led to the same conclusion. An often-quoted rule
of thumb is that costs up to €50,000 per QALY are acceptable (35). At that threshold, the cost utility of usual care
was better than for the RAPIT program, and significantly
so according to the VAS. We conclude that, according to
current societal standards, the exercise classes did not
improve the health valuation of the RA patients sufficiently to provide good value for money.
A number of remarks need to be made that temper the
sharpness of this conclusion. Most importantly, our analysis has not taken into account preventive effects on cardiovascular and fracture risks and the associated cost savings (2), because the available data were insufficient for a
quantitative extrapolation of future participation, effectiveness, damage, and costs. Second, although corrected
for, results may have been influenced by some statistically
significant baseline differences that we attribute to early
dropout among healthier patients randomized to obtain
usual care. Third, the used utility measures may be less
appropriate for evaluation of the health of RA patients in
clinical trials (36), because trials are usually powered for
more sensitive primary outcome measures and patients
continually adjust to their worsening health status (37).
The few economic evaluations of physical therapy in
somewhat similar patient groups either did not include
utility measures (38 – 40) or also found insufficient improvement (41). Finally, the societal perspective ignores
important financial considerations. For example, patients
could be asked to contribute to the amount of what they
would have to pay at a fitness center.
In economic evaluations, effectiveness is preferably estimated using utility measures because they aim to estimate the overall value of a treatment. A remarkable discrepancy revealed in our analysis is that significant and
46
clinically important improvements on the effectiveness
measures targeted by the intervention, like physical capacity and functional ability, did not translate into a significant improvement on the utility measures. There can be
several explanations for this finding. First, utility measures may not be sensitive enough to detect true improvements in overall value or, equivalently, true improvements
in overall value may be too small to be detected by available utility measures. This explanation does not invalidate
their use in economic evaluations, provided that the utility
measures include the relevant domains, as was the case in
our study. Second, the value of the improvements on the
targeted effectiveness measures may be countered by unexpected or unknown changes in other domains, which is
suggested here by the significant difference in the VAS.
To compare the efficiency of different treatments in
rheumatology, disease-specific outcome measures can be
used. We analyzed the primary clinical endpoints of the
study, both measuring functional ability. The HAQ is used
extensively in rheumatology research, but has been reported to be insensitive to changes due to exercise therapy
(7,42). This was confirmed in the RAPIT study. Patients in
the RAPIT group on average showed only a 0.01 improvement on a scale from 0 to 3, at the annual costs of €24,000
per HAQ point. The above-mentioned rule of thumb of
€50,000 per QALY suggests that the estimated costs per
HAQ point are unacceptably high.
The most sensitive measure in our study was the
MACTAR: over the 2-year period, patients following the
RAPIT program had an average MACTAR score that was
2.9 points better than for patients receiving usual care.
Most of the difference in the MACTAR score was attributable to the items that assessed difficulty performing the
individually selected impaired activities. Because the
weighted MACTAR score, on average, assigns 3 points to
these activities, the estimated 2.9 difference can be interpreted as that patients following the RAPIT program had 1
less relevant activity problem, at the annual cost of €630
per problem. Unfortunately, at this moment there are no
data on what constitutes a clinically relevant MACTAR
change, nor is there previous literature to decide whether
the estimated costs per MACTAR point compare favorably
with other interventions in rheumatology.
From the individual patient’s perspective, costs need
not play a role in the decision on whether or not to participate in exercise classes. During the study, most patients
reported personal willingness to pay that was insufficient
to cover the costs (on average €300 annually). Nevertheless
after the study ended, 58% of the patients continued to
follow exercise classes at their own costs for at least a year.
If funding does not provide a problem, then there is no
reason to discourage participation, provided qualified supervision is available to prevent injuries and to adjust the
exercises to individual needs. Moreover, the reduction in
costs for individual physical therapy could provide some
scope for reimbursement.
From an individual patient perspective, there is much to
be said for participating in long-term, high-intensity exercise classes. However, from a societal perspective and
without taking possible preventive health effects into ac-
van den Hout et al
count, they provide insufficient improvement in the valuation of health to justify the additional costs.
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